Artificial tooth.



No. 627,720. Patented 1m 27, I899.

L. F. nurm.

ARTIFICIAL TOOTH.

(Applicgtion filed Mar. 23, 1899.)

(N0 HodeI.)

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% 8 (M/A Z'IFTORNEY UNITED STAT S PATENT OFFICE.

LEONARD F. DUNN, or ONEIDA, NEW YORK.

ARTIFICIAL TOOTH.

SPECIFICATION forming part of Letters Patent No. 627,720, dated June 27,1899;

application filed March 23, 1899.

To all whom it may concern:

Be it known that I, LEONARD F. DUNN, of Oneida, in the county ofMadison, in the State of New York, have inventednew and usefulImprovements in Artificial Teeth, of which the following, taken inconnection with the accompanying drawings, is a full, clear, and exactdescription.

This invention has special reference to the attachment of porcelainveneers to the metal backing which forms part of the main stay oftheartificial tooth when mounted on the crown or bridge.

The object .of my invention is to provide more convenient and moresecure means for attaching the porcelain veneer to the metal backingWithout dangerof injuring the said veneer by the heat imparted to thebacking in the process of applying solder thereto and which improvedattachment shall also permit the veneer to be readily renewed whenrequired and shall also obviate liabilityof mis-- fits of the attachingdevices; and to that end the invention consists in the novelconstruction and combination of parts hereinafter described.

The accompanying drawings illustrate in' segregated and in combinedconditions the component parts of my improved veneer attachment.

Figures 1 and 2 are side and rear face views of the veneer. Figs. 3 and4 are face and edge views of the metal backing. Figs. 5 and 6 are faceand edge Views of the guard-plate which is employed to prevent thesolder from clogging the slots in the metal backing. Fig. 7 is a rearface view of the veneer attached to the metal backing. Fig. 8 is avertical transverse section on line X X in Fig. 7, and Fig. 9 is a sideView of the completed tooth.

My improved veneer-fastening consists of the stud a, which is rigidlysecured to the porcelain veneer b and projects from the back of saidveneer and is formed with a head a on its free end. This veneer isattached to a metal backing 0, consisting of a plate which is providedwith a vertical slot d of uniform width throughout its length andterminating in an enlarged orifice d, usually adjacent to the intendedfree end of the tooth. The plate or backing c is of a thickness equal tothe length of the projecting portion of the of the veneer to thebacking.

Serial No. 710,178. (No model.)

width approximately equal to the thickness of the aforesaid shank, whilethe orifice d is of a diameter approximately equalto the diameter of thehead a of the stud. I preferably provide the backing c with two of theaforesaid slots and orifices and attach to the veneer b a correspondingnumber of studs a, as shown, to obtain a more secure fastening The studsare in the same relative position as the'orifices .d d, and in attachingthe veneer b to the' backin g c the heads a of the studs are passedthrough said orifices and then the veneer b is pushed toward the base ofthe backing c, and in said operation the shanks of the studs slide inthe slots d, while the heads a of the studs bear on the back of thebacking o, and thus effectually interlock the studs with the backing. Bymaking the slots (1 of uniform width throughout their lengths I enablethe backing c to interlock with studs a, located at different distances.from the base of the veneer, and therefore I obviate the liability ofmisfits of the attaching devices of the veneer. The heads a, aresubsequently covered by the body f of solder applied to the v rear faceof the backing c. In order to permit said solder to be applied to thebacking while the veneer b is removed therefrom, and thus obviateheating and injuring the porcelain veneer, I employ a guard-plate e,which I fasten to the rear face of the backing, preferably by means ofsolder, before applying the body f of solder. Said guard-plate isprovided with vertical slots 6 6', each of which is of a widthapproximately equal to the diameter of one of the heads a and ofsufficient length to allow the head to freely travel in the slot 6 inthe operation of applying the veneer to the backing in the mannerhereinbefore described.

In practicing my invention I proceed as follows, to wit: Before applyingthe veneerb to the backing c I temporarily fill the slots 6 e of theguard-plate 6, with a suitable material to exclude from said slots thesolder which is subsequently appliedto the backing to form the innerportion of the tooth, as shown at f in Fig.9 of the drawings. After thishas been accomplished I remove the'aforesaid stop-out material from theslots e e and apply the veneer b to the backing c by putting wax intothe slots in the backing and after warming andsoftening the wax passingthe heads a of the studs a through the orifices d and pushing the veneertoward the opposite ends of the slots d, and thereby causing the heads ato become interlocked with the backing c, as hereinbefore described. Ithen place the backing, with the veneer temporarily secured thereto,upon the crown or bridge and secure it thereon by means of a smallamount of plaster-of-paris placed on the backing and crown or adjacentteeth. I then remove the veneer b from the backing and permanentlysolderthelattertothecrown orbridge. After this is effected I replace theveneer on the backin g in the manner hereinbefore described with cementinterposed between them.

I do not limit'myself to the use of the guardplate 6, inasmuch as thebacking 0 may be made of a plate of suificient thickness to allow theslots d, with the orifices d',to be formed in the plate withoutextending entirely through the plate. Such construction can beaccomplished by means of suitable millingtools. Said guard-plate mayalso be dispensed with where a thin backing is required, as is sometimesthe case on front teeth or when a cheaper class of Work is desired. Insuch cases I remove a portion of the cement after the veneer has beensecured to the backing and fill the space with amalgam covering theheads of the studs.

I do not confine myself to the arrangement of the orifices (1 cl in theend portion of the backing adjacent to the intended free or cutting endof the tooth, as hereinbefore stated, inasmuch as it may be desirable onbridge or dummy teeth to have the aforesaid orifices in the opposite endportion of the backing to allow the veneer to be pushed toward the cutting or grinding end of the tooth in the op'= eration of securing theveneer to the backing.

What I claim as my invention is-- 1. In crown and bridge Work ofartificial teeth the combination, with the veneer front, of the metallicbacking provided with a Vertical slot of uniform width throughout itslength and terminating in an enlarged orifice at one end and a studprojecting from the veneer front and of a diameter approximately equalto the width of the aforesaid slot and formed on its free end with ahead of a diameter approximately equal to the diameter of the aforesaidorifice and larger than the adjacent vertical slot, all constructed topermit the veneer to be fastened to the backing by introducing the headof the aforesaid stud through the orifice in the backing and pushing theveneer vertically on said backing and thereby causing the head of thestud to become interlocked with the backing at opposite sides of thevertical slot thereof substantially as described and shown.

2. In crown and bridge work for artificial teeth the combination, withthe veneer front, of the metal backing provided With a vertical slotterminating in an enlarged orifice at one end, a stud projecting fromthe veneer and of a diameter to permit its slidingin the aforesaid slotand formed on its free end with a head of a diameter to pass through theaforesaid orifice and a guard-plate fastened to the rear face of theaforesaid backing and provided with a vertical slot of a widthapproximately equal to the diameter of the head of the aforesaid studsubstantially as and for the purpose set forth.

LEONARD F. DUNN.

i tn esses LILLIAN J. WRIGHT, XV. L. PARKELL.

